Dental syringe adapter



July 31, 1962 c. SAENZ DENTAL SYRINGE ADAPTER Filed Dec. 19, 1958 Q onmm v mm Q IIN F NM 1 a w 3 NM mm 9 vn M 9m vw n R "W AWE/7 mm Q 2 m mu 3W Came/aria Saenz 1N VEN TOR.

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3filfi35 Patented July 31, 1962 Filed Dec. 19, 1958, Ser. No. 781,523 7Claims. (Cl. 128218) This invention relates to hypodermic syringes andmore particularly to improvements in conventional dental syrines.

The dental patient is always apprehensive to pain when he awaits anextraction and at the time that he sees the type of syringe that ispresently used by dentists. This invention provides a dental syringeadapter which conceals the needle of the syringe and which servesseveral other important functions. The concealing of the needleautomatically prevents at least some of the apprehension in the patient.

The adapter for the dental syringe will reduce pain in the injection. Itis a present practice for dentists to press the index finger of the lefthand on the area of gum tissue to be injected just before inserting theneedle. This pressure applied by the dentists finger reduces the painwhen actual injection takes place. An adapter constructed in accordancewith this invention serves the same purpose and it is entirelyunnecessary for the dentists finger to come in contact with theanesthetic. A number of dentists are constantly bothered with dermatitiscaused by contact of the anesthetic. By use of this adapter, the dentistneed not use his index finger to apply pressure and therefore, he neednot have his finger come in contact with the anesthetic.

An adapter constructed in accordance with the invention is exceedinglysimple from a mechanical standpoint. It includes only three parts and aslight modification of a conventional syringe. The adapter has a gumtissue pressure tip, a syringe barrel sleeve with which the tip isadjustably connected and a spring which reacts on the tip and the bodyof the syringe in a direction to yieldingly maintain the sleeve and tipin an extended position with respect to the syringe.

There is a lock connected with the body of the syringe and the barrelsleeve to hold the barrel sleeve in a selected retracted position whenthis is desired by the dentist or by the person sterilizing theequipment.

Accordingly, it is a further object of the invention to provide asyringe adapter, preferably but not exclusively used by dentists, whichpossesses structurally improved features over previous syringes.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawing forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

FIGURE 1 is a perspective view, parts broken away to illustrateotherwise hidden detail, of a conventional syringe provided with anadapter which is in the extended position with respect to the syringe.

FIGURE 2 is a sectional view taken on the line 22 of FIGURE 1.

FIGURE 3 is an enlarged fragmentary sectional view of the constructionin FIGURE 2, showing the adapter in the retracted position.

FIGURE 4 is a transverse sectional view taken on the line 44 of FIGURE 3and showing the adapter locking structure.

In the accompanying drawing there is a syringe having an elongatedtubular syringe body 12, an ampule 14 containing an anesthetic, aplunger 16 operable in syringe body 12 and other conventional structureordiarily found in a common syringe. Among this other structure is thetubular needle 18 to pierce the ampule, the needle held in place byneedle holder 20 at the outer end of the syringe body. The use of anordinary syringe is well known in the art, and its functions are equallywell known.

This invention improves the conventional syringe by an adapter 22 havinga tip 24, a syringe body sleeve 26 and a coil spring 28. Tip 24 has alongitudinally concave, truncated conical end 30 through which centralpassage 32 extends. The tip has a sleeve portion 34 having externalthreads 36 at its inner end, and a recess 4% divided from passage 32 byshoulder 42. Needle '13 extends through recess 49 and passage 32, butthe normal position of the adapter tip.(FlGURE 2) completely conceal theneedle 18.

Spring 28 is seated on shoulder 42 and on the end wall 44 of syringebody 12. The bias of the spring is in a direction tending to extend theadapter 22 outwardly from the needle end of the syringe. Sleeve 26 abore 48 of sufiicient diameter to fit over the generally cylindricalbody 12 of the syringe. One end of the bore has internal threads 50 inwhich threads 36 are engaged. Tip 24- is adjustable with respect to thesleeve 26 by threading the tip to a deeper or more shallow position inthreads 59.

There is means for locking the sleeve in a selected adjusted position onthe body 12 of the syringe. This means consists preferably of a memberor screw 54 radially adjustable in a threaded opening 56 in the sidewall of sleeve 26. The inner end of the screw may be made to engage inkeeper means in the form of a selected inclined notch or slot 60 in thebody 12 of the syringe 19. The notch 64 is one of a group of notches andis inclined in a direction to keep the screw 54 well seated in thebottom of notch 6i). Hence, the position of the adapter on the body ofthe syringe may be selected by proper selection of notches 61) withinwhich screw 54 seats.

In operation, it is assumed that the syringe is ready for use. In suchposition (FIGURE 2) the adapter is held on the syringe body by means ofscrew 54 seating in a selected notch 69. Spring 28 holds the adapter inplace, but the adapter may be slid back on body 12 as the dentistapplies pressure to the area around the piercing point for needle 18. Aspressure is applied, only the end of adapter tip 24 contacts the tissueof the patient. By application of additional force, the point of needle18 is made to penetrate the tissue inasmuch as the adapter will slideback on the body of the syringe, the screw 54 separating from or ridingat least part of the way out of its notch 64). By depression of plunger16, the injection may be completed.

In cases wherein it is impractical to use the adapter, it need not beseparated from the syringe. It is only necessary to pull the adapterback on the syringe body and engage screw 54 in a different notch 60,holding the adapter inwardly of the syringe against the yieldingopposition of spring 28. Then, the syringe may be used as any otherconventional syringe.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly, all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention asclaimed.

What is claimed as new is as follows:

1. A syringe comprising, in combination, an elongated tubular body forreceiving an ampule, a tubular needle in the forward end portion of thebody for puncturing the ampule for receiving fluid therefrom, means onthe rear end portion of the body for ejecting the fluid through theneedle, a sleeve connected to and slidable longitudinally on the body, atip mounted on' the sleeve and slidable on the needle to a forwardoperative position wherein the needle is concealed and to a rearwardinoperative position wherein said needle is exposed, resilient meansyieldingly urging the tip forwardly on the needle, and means forreleasably anchoring the tip in either position against the tension ofsaid resilient means.

2. A syringe in accordance with claim 1, wherein said resilient meansincludes a coil spring mounted under compression between the forward endof the body and the tip and encircling the needle.

3. A syringe in accordance with claim 1, said body having generallycircumferential slots therein at longitudinally spaced points havingcommunication with each other, said anchoring means including a membermounted on the sleeve and engageable selectively in the slots, saidsleeve being rotatable on the body for engaging the mem-' her in theslots. a

4. A syringe comprising an elongated tubular body for receiving a fluid,a tubular needle in the body communicating therewith for receiving fluidtherefrom, means on the rear end of the body for ejecting the fluid,said body having a longitudinally elongated opening therein and furtherhaving longitudinally spaced, parallel rearwardly opening slotscommunicating at one end with the pening and extending at a forwardinclination therefrom and closed at their. forward ends, a sleeveslidable longitudinally on the body and connected thereto, a tip on thesleeve slidable on the needle to a forward operative position forconcealing same and. to a retracted, inoperative position for exposingsaid needle, a coil spring mounted under compression between the bodyand the tip for yielding urging the latter forwardly, and a member onthe body engageable selectively in the slots for anchoring the tip ineither position. i

5. A syringe comprising an elongated body for the reception of a fluid,a needle projecting from the for ward end of the body, means forejecting the fluid through the needle said body having an openingtherein and further having longitudinally spaced slots thereincommunicat-ing with the opening and extending at a forward inclinationfrom their open ends therefrom, a sleeve connected to and slidable onthe body, a tip'on said sleeve slidable forwardly to an operativeposition on the needle for concealing same, a spring between the tip andthe body for yieldingly actuating and tip forwardly to said operativeposition, and a member mounted in the sleeve and engageable selectivelyin the slots for releasably anchoring the tip in. said operativeposition for concealing the needle .or in a retracted inoperativeposition for exposing the needle. 1 v v 6. A syringe in accordance withclaim 5, wherein said tip is threadedly connected to the sleeve forlongitudinal adjustment relative .to the needle.

7. A syringe in accordance with claim 5, wherein said tip comprises agenerally truncated conical, longitudinally concave shape.

References Cited in the file of this patent UNITED STATES PATENTS

